Improvement in steam-generators



I. BARTON.

Steam Generators.

Patented July 15, 18 73.

i/Wwww AM. mo 10 -umo GRAPH/L ca NY (ossomvsls mu czssa) UNITED STATES ISAAC BARTON, OF WILLIAMSPORT, PENNSYLVANIA.

IMPROVEMENT IN STEAM-GENERATORS.

Specification forming part of Letters Patent No. 140,872, dated July 15, 1873 application filed March 24, 1873. t

To all whom it may concern:

Be it known that I, ISAAG BARTON, of Williamsport, in the county of Lycoming and State of Pennsylvania, have invented an Improvement in Steam-Boilers, of which the following is a specification:

This invention mainly relates to return-flue I tubular boilers, having a fire-box within them,

a longitudinal vertical section of a boiler constructed in accordance with my improvement 5 Fig.2, a transverse vertical section on the line aw,- and Fig. 3, a similar section on the line 3 3 but looking in a reverse direction.

Similar letters of reference indicate corresponding parts.

The boiler represented in the drawing is a double return horizontal tubular one of the locomotive or portable kind, but the crownsheet A is of a convex shape, struck from a center above, and of the width of the fire-box B down within which it projects. This shape of the crown-sheet is preferable to a concave one arching upward, inasmuch as not only is that strength obtained which is due to a cylindrical boiler, without the aid of braces or stays, but there is an increased heating-surface as compared with a fiat crown-sheet, and the capacity of the boiler may be enlarged without increasing the width of the outside shell or lengthening the latter or flues of the boiler, but by simply lengthening the sides or waterspaces 0 Q and bringing the crown-sheet A further down so as to admit of an increased number of tubes or flues being inserted. On board boats, and where room is an object,this is an important consideration. D is the grate, E the fire-door, and F the ash-pit. G G are the fire-box tubes or flues,and H the back tube-sheet thereof, connected above so as to form an attachment at right angles or thereabout, with an upper crown-sheet, I.

The fire and heated gaseous products of combustion first return along the fire-box flues G G into a front smoke-box, K, and from thence back through an upper or second set of longer return-tubes, L L, into a rear smoke-box, S, which connects with the chimney. M M represent a row or rows of drop-tubes connected through the upper crown-sheet I with the water-space above. These tubes, which are exposed to the full action of the flame from or in the fire-box, are fitted with circulating pipes b on their inside, open at their bottoms, while the tubes are closed at their lower ends to keep up a circulation and prevent collection of mud or sediment in the tubes. Said drop-tubes add to the capacity of the boiler without adding to the room occupied by the latter. N is a steam-dome, on which may be a man-head, safety-valve, and branch steampipe. 0 is a plate at back of the ash-pit, having a'projection on it to carry the grate. This plate may be fitted with a slide or damper to admit cold air into a perforated box or chamber, 1?,beneath and in rear of the bridgewall Q, to assist in the combustion of the gases when needed, andwhich air, by the arrangement shown,will be properly heated to give the best results on mixing with the gases. R R are cross-braces for strengthening the boiler at points above the lower return-tubes or flues'. Other stays may also be used, if desired, and the seam of the crown-sheetAeither be turned upward or downward, as preferred.

The crown-sheet is shown as inclining downward in a rearward direction, to give increased water capacity where the fire is hottest.

The bridge-wall Q is made hollow to form a water-space in communication with the water legs or sides 0 G. This not only gives increased heating-surface, but promotes circulation. There may be any number of such tubular connections, one in rear of the other. T is a blow-pipe, connecting with the boiler through the lower back portion of the crownsheet A, and projecting through the rear water leg or side of the boiler, the same serving to carry oft mud or sediment collecting on the crown-sheet A,

1 Gimme In some easesas, for instance, in boilers for sea-going steamersa single and enlarged upper shell surface, V, may be made to take in or cover two, three, or more convex crownsheets A and water legs or side spaces between them, as well as outside water-spaces, with a like arrangement of return tubes or flues and accompanying parts heretofore described.

What is here claimed, and desired to be secured by Letters Patent, is-

1. The combination of the double set of return-fines G L, the front and rear smoke-boxes K S, the fire-box B, the crown-sheet A, the

water legs or sides 0, the back tube-sheet H,

and the upper back crown-sheet I, when said scribing witnesses.

ISAAG BARTON.

Witnesses:

FRED HAYNES, D. MISELL. 

